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DOE OSTI · 1813121

Flux-pumped impedance-engineered broadband Josephson parametric amplifier

Grebel, J.·Bienfait, A.·Dumur, É.·Chang, H. -S.·Chou, M. -H.·Conner, C. R.·Peairs, G. A.·Povey, R. G.·Zhong, Y. P.·Cleland, A. N.
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Abstract

Broadband quantum-limited amplifiers play a critical role in the single-shot readout of superconducting qubits, but a popular implementation, the traveling wave parametric amplifier, involves a complex design and fabrication process. Here, we present a simple design for a Josephson parametric amplifier, using a lumped element resonator comprising a superconducting quantum interference device whose useful bandwidth is enhanced with an on-chip impedance-matching circuit. Additionally, we demonstrate a flux-coupling geometry that maximizes the coupling to the Josepson loop and minimizes spurious excitation of the amplifier resonant circuit. The amplifier, which operates in a flux-pumped mode, is demonstrated with a power gain of more than 20dB over a bandwidth of about 300MHz, where approximate noise measurements indicate quantum-limited pehrformance. A procedure is given for optimizing the bandwidth for this kind of amplifier, using a linearized circuit simulation while minimizing non-linearities.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSQuantum computingacoustic noise measurementamplifiersmicrowave frequenciessignal processingsuperconducting quantum interference device

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Grebel, J., Bienfait, A., Dumur, É., Chang, H. -S., Chou, M. -H., Conner, C. R., Peairs, G. A., Povey, R. G., Zhong, Y. P., Cleland, A. N.. 2021-04-05. Flux-pumped impedance-engineered broadband Josephson parametric amplifier. https://doi.org/10.1063/5.0035945

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